The advantage of suspending boat fenders over the sides of boats to protect the hull from damage caused by collision against adjacent moorings has long been recognized. In order to minimize the effective vertical length necessary for such boat fenders, however, frequent relative vertical adjustment of those boat fenders is often necessary in order to accommodate tidal and mooring-height variations.
Deck cleats and other rope fastening means have often been used to anchor and suspend boat fenders over the sides of boats equipped therewith. Unfortunately, tying and untying ropes from those cleats or other anchoring devices is time consuming and awkward, particularly during docking maneuvers when the appropriate positioning of the boat fenders may first be ascertained, and when their appropriate positioning is of vital importance. Additionally, while deck cleats are often able to satisfactorily anchor these fenders once the lashing operation is completed, upon unlashing of the fender ropes therefrom, the entire weight of the boat fender must often be supported entirely by the sailor who is adjusting same, thereby presenting a possibility that the fender may be dropped into the water during this adjustment process.
More recently, other types of fender anchors or cleats have been provided which are intended to eliminate the tying and untying of fender lines during the adjustment of those fenders. While these fender line anchors or cleats have experienced some degree of success, they are often expensive, limited to use with particular fender line sizes or types, increase fender line wear, are awkward, and retain and release the fender lines for adjustment with varying degrees of effectiveness. Additionally, many of those cleats or anchors which are available are relatively complex, comprising many parts, springs, etc. which are particularly prone to corrosive attack when used in or around salt water.
Adjustable rope anchors or cleats are, of course, known for other than marine applications. Examples of one piece anchors are, for example, disclosed in U.S. Pat. Nos. 338,037 (Clow); 678,533 (Bancker); 837,247 (Nuttall); 1,044,805 (Normand); 1,546,798 (Seagren); 3,736,925 (Erman); British Specification No. 14,386, dated 1911 (Bromfield) and British Specification No. 8544, dated 1897 (Humphreys).